Tool holder assembly

ABSTRACT

A tool holder assembly including a cutting tool, a tool holder, and an adapter. The cutting tool includes a fluid passage and an end portion. The tool holder includes a conduit and a counterbore adapted to receive the cutting tool. The adapter includes a tool receiving portion configured to receive the end portion and an internal fluid passage adapted to provide a fluid from the conduit to the fluid passage.

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates to a tool holder assembly, and moreparticularly to a tool holder assembly incorporating an adapterconfigured to deliver a fluid to a cutting tool.

2. Background Art

Previously, drill chucks incorporated a fluid supply hole adapted toreceive a straight shank of an oil-through-drill, as described in U.S.Pat. No. 5,649,714. In that patent, a seal block was positioned in thefluid supply hole to regulate fluid flow into a fluid channel of theoil-through-drill and into a gap portion between the fluid supply holeand the straight shank portion. Such drill chucks did not address thedesirability of gap-free sealing between a cutting tool and an adapterto inhibit fluid leakage and improve tool life. Moreover, such drillchucks were not configured for use with a minimum quantity lubrication(MQL) machining system in which very limited amounts of lubricant areprovided at high pressure to the cutting surfaces of the cutting tool tosustain the machining process. In addition, such chucks did notincorporate adjustment screws to facilitate the axial positioning of thecutting tool.

Before Applicants' invention, there was a need for a tool holderassembly that was compatible with an MQL machining system andfacilitated the supply of pressurized fluid to the cutting surfaces of acutting tool while inhibiting fluid leakage. In addition, there was aneed to incorporate the functionality of an adjustment screw toaccurately position the cutting tool without the need to manufacture,position, and install a separate adjustment screw component. Problemsassociated with the prior art as noted above and other problems areaddressed by Applicants' invention as summarized below.

SUMMARY OF INVENTION

According to one aspect of the present invention, a tool holder assemblyis provided. The tool holder assembly includes a cutting tool, a toolholder, and an adapter. The cutting tool includes a main portion, an endportion, and a fluid passage. The main portion has a first diameter. Theend portion has a second diameter and is disposed proximate the mainportion. The fluid passage is disposed in the main and end portions. Thetool holder includes a conduit and a counterbore. The counterbore isadapted to receive the cutting tool and is axially aligned with theconduit. The adapter includes a tool receiving portion, a body portion,and an internal fluid passage. The tool receiving portion is configuredto receive the end portion. The body portion is disposed proximate thetool receiving portion and is adapted to engage the conduit. Theinternal fluid passage is defined by the tool receiving and bodyportions and is adapted to provide a fluid from the conduit to the fluidpassage.

The internal fluid passage may include a chamfer disposed proximate thetool receiving portion that is adapted to direct fluid to the fluidpassage.

The adapter may include a first internal fluid passage disposed in thebody portion and a second and third internal fluid passages disposed inthe tool receiving portion proximate the first internal fluid passage.

The counterbore may include a bottom surface. A spring may be disposedbetween the tool receiving portion and the bottom surface for biasingthe adapter against the end portion.

A seal may be disposed between the end portion and the tool receivingportion for inhibiting fluid leakage.

According to another aspect of the present invention, a tool holderassembly is provided. The tool holder assembly includes a cutting tool,a tool holder, an adapter, and a spring. The cutting tool includes amain portion, an end portion, and a fluid passage. The main portion hasa first diameter. The end portion has a second diameter. The fluidpassage is disposed in the main and end portions. The tool holder isconfigured to rotate about an axis of rotation and includes a conduitand a counterbore. The counterbore is adapted to receive the cuttingtool and has a bottom surface. The adapter includes a tool receivingportion, a body portion, and an internal fluid passage. The toolreceiving portion is configured to receive the end portion. The bodyportion is disposed proximate the tool receiving portion and is adaptedto engage the conduit. The internal fluid passage is defined by the toolreceiving and body portions and is adapted to provide a fluid from theconduit to the fluid passage. The spring is configured to bias theadapter against the cutting tool to inhibit fluid leakage.

The adapter may be configured to flex about the axis of rotation tofacilitate insertion of the adapter into the conduit.

According to another aspect of the present invention, a tool holderassembly is provided. The tool holder assembly includes a cutting tooland a tool holder. The cutting tool includes a main portion and anadapter portion. The main portion has a first diameter and a first fluidpassage. The adapter portion is disposed proximate the main portion andhas a second diameter and a second fluid passage disposed coaxially withan axis of rotation and connected to the first fluid passage. The toolholder includes a conduit and a counterbore. The conduit is adapted toreceive the adapter portion and provide a fluid to the second fluidpassage. The counterbore is adapted to receive the cutting tool and isaxially aligned with the conduit.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a section view of a first embodiment of a tool holderassembly.

FIG. 2 is a section view of a second embodiment of the tool holderassembly.

FIG. 3 is a section view of a third embodiment of the tool holderassembly.

FIG. 4 is a section view of a fourth embodiment of the tool holderassembly.

DETAILED DESCRIPTION

Referring to FIG. 1, one embodiment of a tool holder assembly 10 isshown. In this embodiment, the tool holder assembly 10 includes acutting tool 12, a tool holder 14, and an adapter 16.

The cutting tool 12 includes a shank or main portion 20, an end portion22, one or more cutting surfaces 24, and one or more fluid passages 26.The cutting tool 12 may have any suitable configuration and may be ofany suitable type, such as a chamfer tool, counterbore, drill, mill,reamer, or tap.

The end portion 22 is disposed proximate the main portion 20. The endportion 22 may have any suitable configuration for mating with theadapter 16. In the embodiment shown in FIG. 1, the end portion 22 has amale configuration and a smaller diameter than the main portion 20. Inaddition, the end portion 22 may have a generally planar, contoured, orchamfered end surface that helps position or center the cutting tool 12.

The fluid passages 26 extend through the cutting tool 12 and areconfigured to provide a fluid proximate the cutting surface 24. Thefluid passages 26 may have any suitable configuration. In the embodimentshown in FIG. 1, the fluid passages 26 are aligned generally parallel toand spaced apart from an axis of rotation 28.

The tool holder 14 is configured to hold the cutting tool 12 and rotateabout the axis of rotation 28. More specifically, the tool holder 14 isconfigured to be connected to a spindle or other suitable device that isadapted to rotate the tool holder 14. The tool holder 14 may be of anysuitable type, such as shrink fit holder or chuck. Also, the tool holder14 may be made of any suitable material, such as a polymeric material ora metal.

The tool holder 14 includes a counterbore 30 and a conduit 32. Thecounterbore 30 is adapted to receive the cutting tool 12 and includes abottom surface 34. The counterbore 30 may have any suitableconfiguration for receiving and holding the cutting tool 12. Optionally,the cutting tool 12 may be secured to the tool holder 14 in any suitablemanner, such as with one or more set screws as is known by those skilledin the art.

The conduit 32 is adapted to provide a fluid to the cutting tool 12. Forexample, the conduit 32 may be connected to a fluid supply pipe or fluidsource that is adapted to provide any suitable fluid, such as a coolantor lubricant in the form of an aerosol, gas, or liquid. The conduit 32may have any suitable configuration. For example, the conduit 32 may beintegrally formed with the tool holder 14, may be a separate componentattached to and extending through the tool holder 14, or may be definedby a combination of integrally formed tool holder surfaces and separatecomponents. In the embodiment shown in FIG. 1, the conduit 32 includes anarrow portion 36 of the tool holder 14 and a pipe 38 coupled to thetool holder 14 with a fastener 40. Also, the conduit 32 may be disposedconcentrically with the axis of rotation 28 and may have a smallerinside diameter than the counterbore 30.

The adapter 16 includes a body portion 50 and a tool receiving portion52. The adapter 16 is configured to receive the end portion 22 toinhibit fluid leakage and help position the cutting tool 12. The adapter16 may be made of any suitable material, such as a polymeric material ora metal.

The body portion 50 and the tool receiving portion 52 cooperate todefine an internal fluid passage 54. The internal fluid passage 54 maybe disposed coaxially with the conduit 32.

The body portion 50 is adapted to engage the conduit 32. Morespecifically, the body portion 40 may be configured to attach to or sealagainst the inside of the conduit 32 to inhibit fluid leakage. The bodyportion 50 may have any suitable configuration. In the embodiment shownin FIG. 1, the body portion 50 includes a first section 56 disposedproximate the pipe 38 and a second section 58 disposed proximate thenarrow portion 36. Alternatively, the second section 58 may be omittedand the first section 56 may extend from the bottom surface of the toolreceiving portion 52. Optionally, the first or second sections 56,58 mayhave a threaded portion disposed on an exterior surface.

The tool receiving portion 52 may include a socket or recess 60 adaptedto receive the cutting tool 12. More specifically, the recess 60 mayhave a similar configuration as the end portion 22. Optionally, therecess 60 may have a larger outside diameter than the body portion 50 tohelp position the adapter 16 within the counterbore 30.

The adapter 16 may include a chamfer 62 disposed in the recess 60proximate the internal fluid passage 54 to improve fluid flow and fluiddistribution to the fluid passages 26. More particularly, the chamfer 62and centrifugal forces present when the tool holder assembly 10 isrotated cooperate to direct fluid from the internal fluid passage 54outward to the fluid passages 26.

Optionally, a seal 70 may be disposed between the tool receiving portion52 and the end portion 22 to further inhibit fluid leakage. The seal 70may have any suitable configuration. In one embodiment, the seal 70 isat least partially disposed in a groove located on the end portion 22 orthe tool receiving portion 52.

In addition, adapters having different configurations may be associatedwith each type or size of cutting tool. For example, adapters whereinthe first and/or second sections 56,58 have different geometries orcross-sections for each tool may be employed to help insure that thecorrect adapter is used with a particular cutting tool.

Referring to FIG. 2, a second embodiment of the tool holder assembly 100is shown. In this embodiment, the tool holder assembly 100 includes acutting tool 112 and a tool holder 114 having an integral adapterportion 116.

The cutting tool 112 includes a main portion 120, one or more cuttingsurfaces 124, one or more fluid passages 126, and may be rotatable aboutan axis of rotation 128 as previously described.

The tool holder 114 includes a counterbore 130 and a conduit 132. Thecounterbore 130 has a bottom surface 134. The conduit 132 may have anysuitable configuration and may include a narrow portion 136 and/or apipe 138 coupled to the tool holder 114 with a fastener 140 aspreviously described.

The adapter portion 116 includes an internal fluid passage 154. In theembodiment shown in FIG. 2, the internal fluid passage 154 also extendspartially into the main portion 120. The adapter portion 116 may alsohave a first section 156 disposed proximate the pipe 138 and a secondsection 158 disposed proximate the narrow portion 136.

A chamber 160 may connect the internal fluid passage 154 and the toolfluid passages 126. The chamber 160 may include a tapered surface orchamfer 162 to improve flow and distribution to the fluid passages 126as previously described.

Referring to FIG. 3, a third embodiment of the tool holder assembly 200is shown. Similar to FIG. 1, the tool holder assembly 200 includes acutting tool 212, a tool holder 214, and an adapter 216.

The cutting tool 212 may include a main portion 220, one or more cuttingsurfaces 224, a plurality of fluid passages 226, and may be rotatableabout an axis of rotation 228 as previously described.

The tool holder 214 includes a counterbore 230 and a conduit 232. Thecounterbore 230 has a bottom surface 234. The conduit 232 may have anysuitable configuration and may include a narrow portion 236 and/or apipe 238 coupled to the tool holder 214 with a fastener 240 aspreviously described.

The adapter 216 may include a body portion 250 and a tool receivingportion 252, as previously described. The body portion 250 may alsoinclude a first internal fluid passage 254, a first section 256 disposedproximate the pipe 238 and a second section 258 disposed proximate thenarrow portion 236.

The tool receiving portion 252 includes a plurality of additional fluidpassages. In one embodiment, the tool receiving portion 252 includessecond and third internal fluid passages 260,262 connected to the firstinternal passage 254 and to different tool fluid passage 226. The firstand/or second internal fluid passages 260,262 may be angled or include acurved or tapered surface to improve fluid flow and distribution to thetool fluid passages 226.

Referring to FIG. 4, a fourth embodiment of the tool holder assembly 300is shown. In this embodiment, the tool holder assembly 300 includes acutting tool 312, a tool holder 314, an adapter 316, and a spring 318.

The cutting tool 312 may include a main portion 320, an end portion 322,one or more cutting surfaces 324, one or more fluid passages 326, andmay be rotatable about an axis of rotation 328 as previously described.

The tool holder 314 includes a counterbore 330 and a conduit 332. Thecounterbore 330 has a bottom surface 334. The conduit 332 may include anarrow portion 336 and/or a pipe 338 coupled to the tool holder 314 witha fastener 340.

The adapter 316 may include a body portion 350, a tool receiving portion352, and an internal fluid passage 354, a first section 356, a secondsection 358, a recess 360, and a chamfer 362 as previously described.

The spring 318 is adapted to engage the tool receiving portion 352 andthe bottom surface 340 to bias the adapter 316 into engagement with theend portion 322 to position the tool and inhibit fluid leakage.

The tool holder assemblies 10,100,200,300 described above may beemployed with any suitable machining process or fluid delivery system.For example, the tool holder assemblies 10,100,200,300 may be used witha minimum quantity lubrication (MQL) system. In an MQL system, apressurized lubricating fluid, such as an oil mist, is provided throughthe tool holder 14,114,214,314 and cutting tool 12,112,212,312 to thecutting surfaces 24,124,224,324. Fluid delivery is controlled to providejust enough lubrication to sustain the machining process. Consequently,it is desirable to provide gap-free sealing between the cutting tool12,112,212,312 and the adapter 16,216,316 or conduit to inhibit fluidleakage and improve tool life. Providing gap-free sealing without manualintervention or manual adjustments to a tool positioning screw isdesirable to help insure quality of the finished part. For example,gap-free sealing without manual adjustments is desirable in processesthat “reuse” tools by regrinding or resharpening cutting surfaces andthereby alter the tool length.

While the best mode for carrying out the invention has been described indetail, those familiar with the art to which this invention relates willrecognize various alternative designs and embodiments for practicing theinvention as defined by the following claims.

1. A tool holder assembly comprising: a cutting tool including: a mainportion; an end portion disposed proximate the main portion; and a fluidpassage disposed in the main and end portions; a tool holder including:a conduit; and a counterbore axially aligned with the conduit andadapted to receive the cutting tool; and an adapter including: a toolreceiving portion configured to receive the end portion; a body portiondisposed proximate the tool receiving portion and adapted to engage theconduit; and an internal fluid passage defined by the tool receiving andbody portions that is adapted to provide a fluid from the conduit to thefluid passage.
 2. The tool holder assembly of claim 1 wherein theinternal fluid passage further includes a chamfer disposed proximate thetool receiving portion and adapted to direct a fluid to the fluidpassage.
 3. The tool holder assembly of claim 1 wherein the adapterfurther comprises a first internal fluid passage disposed in the bodyportion and second and third internal fluid passages disposed in thetool receiving portion proximate the first internal fluid passage. 4.The tool holder assembly of claim 1 wherein the counterbore furthercomprises a bottom surface disposed proximate the conduit.
 5. The toolholder assembly of claim 4 further comprising a spring disposed betweenthe tool receiving portion and the bottom surface for biasing theadapter against the end portion.
 6. The tool holder assembly of claim 1further comprising a seal disposed between the end portion and the toolreceiving portion for inhibiting fluid leakage.
 7. A tool holderassembly comprising: a cutting tool including: a main portion having afirst diameter; an end portion having a second diameter; and a fluidpassage disposed in the main and end portions; a tool holder configuredto rotate about an axis of rotation including: a conduit; and acounterbore adapted to receive the cutting tool and having a bottomsurface; and an adapter including: a tool receiving portion configuredto receive the end portion; a body portion disposed proximate the toolreceiving portion and adapted to engage the conduit; and an internalfluid passage defined by the tool receiving and body portions that isadapted to provide a fluid from the conduit to the fluid passage; and aspring configured to bias the adapter against the cutting tool toinhibit fluid leakage.
 8. The tool holder assembly of claim 7 whereinthe spring is configured to engage the bottom surface and the toolreceiving portion.
 9. The tool holder assembly of claim 7 wherein theinternal fluid passage further includes a chamfer disposed proximate thetool receiving portion and adapted to direct a fluid to the fluidpassage.
 10. The tool holder assembly of claim 7 wherein the adapterfurther comprises a first internal fluid passage disposed in the bodyportion and second and third internal fluid passages disposed in thetool receiving portion proximate the first internal fluid passage. 11.The tool holder assembly of claim 7 further comprising a seal disposedbetween the end portion and the tool receiving portion for inhibitingfluid leakage.
 12. The tool holder assembly of claim 7 wherein thesecond diameter is configured to flex about the axis of rotation tofacilitate insertion of the adapter into the conduit.
 13. The toolholder assembly of claim 7 wherein the first diameter is larger than thesecond diameter.
 14. The tool holder assembly of claim 7 wherein the endportion further includes a first fluid passage and the main portionfurther comprises a plurality of branch fluid passages disposed aboutthe axis of rotation and a chamber disposed proximate the first fluidpassage and the plurality of branch fluid passages.
 15. The tool holderassembly of claim 14 wherein the chamber has a tapered surface fordirecting fluid flow from the first fluid passage to the plurality ofbranch fluid passages.
 16. A tool holder assembly comprising: a cuttingtool including: a main portion having a first fluid passage; an adapterportion disposed proximate the main portion, the adapter portion havinga second fluid passage disposed coaxially with an axis of rotation andconnected to the first fluid passage; and a tool holder including: aconduit adapted to receive at least a portion of the adapter portion andprovide a fluid to the second fluid passage; and a counterbore axiallyaligned with the conduit and adapted to receive the cutting tool. 17.The tool holder assembly of claim 16 wherein the main portion has afirst diameter, the adapter portion has a second diameter, and the firstdiameter is greater than the second diameter.
 18. The tool holderassembly of claim 16 wherein the adapter portion is configured to flexabout the axis of rotation to facilitate insertion of the adapterportion into the conduit.
 19. The tool holder assembly of claim 16wherein the main portion further comprises a plurality of branch fluidpassages disposed about the axis of rotation and a chamber disposedproximate the second fluid passage and the plurality of branch fluidpassages.
 20. The tool holder assembly of claim 19 wherein the chamberhas a tapered surface for directing fluid flow from the second fluidpassage to the plurality of branch fluid passages.